moe1965 750 #1 Posted December 12, 2021 (edited) I got the engine all torn apart for rebuild I found that someone has rebuilt it before. It had a .010 pistons in it. I'm not sure if they did the rebuild correctly or if the rings just got worn completely out but I came up with a measurement of .265 for ring end gap 17/64 of an inch. Middle ring was .125. 1/8 in .No wonder she was blowing smoke. Edited December 12, 2021 by moe1965 More info 2 Share this post Link to post Share on other sites
Maxwell-8 4,366 #2 Posted December 12, 2021 (edited) That is an insane amount of ring gap! I also see quite a lot of squoring probably didn't hone the cylinderwall before assembly Edited December 12, 2021 by Maxwell-8 Share this post Link to post Share on other sites
ebinmaine 69,687 #3 Posted December 12, 2021 WOWOWOW Share this post Link to post Share on other sites
RED-Z06 2,379 #4 Posted December 12, 2021 Might be std rings in a +.010 bore. I put new rings in an M10 That wasnt flushed properly and 2hrs of running the rings had .025 gaps and she was huffing oil 1 Share this post Link to post Share on other sites
ri702bill 8,704 #5 Posted December 12, 2021 Hmmm.... mayhaps someone used stock diameter rings in a .010 overbore??? Sounds so ..... Bill Share this post Link to post Share on other sites
lynnmor 7,471 #6 Posted December 12, 2021 Probably the wrong rings. Is there a ridge at the top of the bore indicating cylinder wear? Is your air filter doing a complete job of filtering all of the air? Share this post Link to post Share on other sites
moe1965 750 #7 Posted December 12, 2021 (edited) I'm not gona take her behind the barn yet and put her down.she is on three legs at the time but I can save her.🤣 Edited December 12, 2021 by moe1965 2 2 Share this post Link to post Share on other sites
953 nut 56,717 #8 Posted December 13, 2021 (edited) How did the piston fit inside the bore, tight or sloppy? You need to take the block to a good machine shop and have the bore measured to know where to begin. I am using numbers from a K-241 (M-10). The end gap is supposed to be .007 to .017 and the difference in circumference from standard rings to .010 over would be about .31416" so I don't think they are standard rings. Here is a bit of math from a post I did a while back. Changes in the ring end gap will be a change to the circumference. Bore changes would be a change in diameter. Because circumference is related to diameter, we can use that ratio to find a missing value. Suppose you know the diameter of a circle but need to find its circumference. Circumference, C, can be placed in a ratio with diameter, d, with the answer pi, π (3.1416). We can rewrite that relationship: C = π x d standard bore of the K-241 cylinder is 3.25" multiplied by Pi gives a circumference of 10.2102" plus standard end gap (.007 to .017). If this block was over bored by .010 the diameter would be 3.35" and the circumference would be 10.5244" plus end gap. The difference of circumference is 0.31416" plus standard end gap, that would be the amount of end gap you could expect to see if the bore were increased by 0.010 and standard rings were used. Not too sure the cylinder is 10 over. https://www.wheelhorseforum.com/topic/87275-can-i-just-hone-this-cylinder/?tab=comments#comment-876680 Edited December 13, 2021 by 953 nut Share this post Link to post Share on other sites
RED-Z06 2,379 #9 Posted December 13, 2021 The rings look pretty thin...might have been dusted Share this post Link to post Share on other sites
953 nut 56,717 #10 Posted December 13, 2021 I wouldn't buy any new parts until the bore has been measured by an experienced machinist. Share this post Link to post Share on other sites
moe1965 750 #11 Posted December 13, 2021 That's easy I'm doing today after work. Taking it to a machine shop and get my measurements and go from there.im sure 'll have a few questions when I get the rebuild under way. 1 Share this post Link to post Share on other sites
